影响Denis B型胸腰椎爆裂骨折内固定术后疗效的相关因素分析

The analysis of prognostic relative factors in patients with Denis type B thoracolumbar fractures after internal fixation

[目的]探讨影响胸腰椎爆裂骨折行切开复位内固定术后矫正度丢失的主要临床相关因素。[方法]回顾性分析2006年1月～2011年7月行切开复位内固定术的Denis B型胸腰椎爆裂骨折的临床资料,以末次随访Cobb角丢失为结局指标,对术后疗效进行随访评定。采用Logistic回归模型对性别、年龄、手术持续时间、内固定方式、植骨方式、术前Cobb角度、术前伤椎前缘高度、伤椎前缘高度改变及伤椎上缘椎间隙高度改变等因素与术后Cobb角度丢失的相关性进行分析。[结果]本研究共纳入48例患者,随访时间11～27个月(平均17.1个月),术后21例Cobb角度丢失≤3°、27例≥4°,Logistic回归分析结果显示,短节段6钉固定术后在Cobb角度维持上较短节段4钉固定效果好(OR=0.160;95%Cl:0.503～0.819;P=0.016),术后进行合理的功能锻炼有利于后凸角度矫正的维持(OR=14.214;95%Cl:0.543～0.843;P=0.005)。[结论]内固定方式及功能锻炼情况是影响胸腰椎爆裂骨折术后Cobb角度丢失的主要因素。伤椎置钉联合短节段椎弓根螺钉内固定治疗胸腰椎爆裂骨折较单纯短节段椎弓根钉固定能更好地维持术后矫正效果,合理的功能锻炼有助于预防术后Cobb角度的丢失。

[ Objective I To explore the clinical relative factors on the the loose of correction in patients with Denis type B thoracolumbar fractures treated with internal fixation. [ Method ] Consecutive patients of Denis type B thoracolumbar fractures treated surgically with open reduction and internal fixation admitted from January 2006 to July 2011 were collected retrospectively. The loose of sagital Cobb angle was made as the primary outcome variable, the following were assessed ： the postoperative efficacy at the follow-up, and non-conditional Logistic regression was used to analyze the correlation of the loose of Cobb angle with patients＇ age, gender, time of operation, methods of internal fixation, sagital Cobb angle, anterior vertebral body height. [ Result] In this study,48 patients meeting the inclusion were collected. The follow-up time was 11 to 27 months （mean follow-up 17.1 months）. The result of the loose of sagital Cobb angle ： angle loose of 21 patients were less than or equal to 3 degrees, that of 27 patients were equal or greater than 4 degrees. Monovariant and muhivariant Logistic regression analysis demonstrated that uniting short segment pedicle screw instrumentation with pedicle screw implanting in injured vertebra to treat thoracolumbar fractures made for the maintain of correction （OR = 0. 160,95 % CI：0.503 -0.819, P = 0.016）, so did reasonable exercises after operation（ OR = 14. 214,95% CI：0.543 -0. 843 ,P = O. 005 ）. [ Conclusion] The style of internal fixation and situation of exercises after operation are the influential factors of the loose of correction in Denis type B thoracolumbar fractures. Six pedicle screws fixation is better than four pedicle screws fixation in maintaining sagital Cobb angle. Reasonable exercises could prevent the loose of Cobb angle.